1. Field
Embodiments of the present disclosure relate to a washing apparatus and a controlling method thereof, and more particularly, to a washing apparatus having an uncontrolled driving motor, and a controlling method thereof.
2. Description of the Related Art
In general, a washing apparatus is an apparatus which washes laundry using a frictional force between the laundry and water, and may be classified into a front load type washing apparatus and a top load type washing apparatus.
In the front load type washing apparatus, a washing operation is performed using a dropping of the laundry while a rotating tub accommodating the laundry is rotated. In the top load type washing apparatus, a pulsator which generates a water stream at a bottom of the rotating tub together with the rotating tub accommodating the laundry is provided, and a washing operation is performed using the water stream generated by the pulsator.
Also, in both of the front load type washing apparatus and the top load type washing apparatus, the laundry is spin-dried using a centrifugal force generated by rotation of the rotating tub.
As described above, the washing apparatus is operated using the rotation of the rotating tub or the pulsator. The washing apparatus widely uses a motor as a device providing a rotating force to the rotating tub or the pulsator.
The motor which is widely used in the washing apparatus may be classified into a controlled motor (a so-called servo-motor) which precisely controls a rotating speed of the motor, and an uncontrolled motor which does not control the rotating speed of the motor.
The controlled motor includes a speed sensor which detects the rotating speed of the motor, and a current sensor which detects a driving current of the motor, and precisely controls the driving current according to the detected rotating speed of the motor. Such a controlled motor may precisely control the rotating speed of the motor regardless of a load.
However, the uncontrolled motor controls the rotation of the motor through an on-time when power is supplied to the motor and an off-time when the power supply to the motor is cut. Such an uncontrolled motor has a relatively low price.
When the washing apparatus includes the uncontrolled motor, it is difficult to precisely control the rotating speed of the motor, and thus a resonance phenomenon may occur continuously during a spin-drying process. Here, the resonance phenomenon means a phenomenon in which a vibration frequency of the rotating tub coincides with a rotation frequency formed by the motor during the spin-drying process and thus the rotating tub is vibrated violently.
In the case of the washing apparatus using a conventional uncontrolled motor, since the rotation of the rotating tub is controlled through only the on-time and off-time of the motor, it is difficult to avoid the resonance phenomenon of the rotating tub.